Geomorphological Evolution of the Plain Between the Livenza And
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Journal of Maps ISSN: (Print) 1744-5647 (Online) Journal homepage: https://www.tandfonline.com/loi/tjom20 Geomorphological evolution of the plain between the Livenza and Piave Rivers in the sixteenth and seventeenth centuries inferred by historical maps analysis (Mainland of Venice, Northeastern Italy) Paola Furlanetto & Aldino Bondesan To cite this article: Paola Furlanetto & Aldino Bondesan (2015) Geomorphological evolution of the plain between the Livenza and Piave Rivers in the sixteenth and seventeenth centuries inferred by historical maps analysis (Mainland of Venice, Northeastern Italy), Journal of Maps, 11:2, 261-266, DOI: 10.1080/17445647.2014.947341 To link to this article: https://doi.org/10.1080/17445647.2014.947341 © 2014 Aldino Bondesan View supplementary material Published online: 12 Aug 2014. Submit your article to this journal Article views: 567 View related articles View Crossmark data Citing articles: 8 View citing articles Full Terms & Conditions of access and use can be found at https://www.tandfonline.com/action/journalInformation?journalCode=tjom20 Journal of Maps, 2015 Vol. 11, No. 2, 261–266, http://dx.doi.org/10.1080/17445647.2014.947341 SCIENCE Geomorphological evolution of the plain between the Livenza and Piave Rivers in the sixteenth and seventeenth centuries inferred by historical maps analysis (Mainland of Venice, Northeastern Italy) ∗ Paola Furlanettoa and Aldino Bondesanb aAkeo, Padova, Italy (private company); bDepartment of Geosciences, University of Padova, Padova, Italy (Received 2 September 2013; resubmitted 14 July 2014; accepted 18 July 2014) The ancient hydrographical network and geomorphological framework of the fluvial and coastal plain encompassed between the Livenza and Piave Rivers in the mainland of Venice (Northeastern Italy) were reconstructed, based on historical maps, georeferenced, and overlaid on available geomorphological maps and aerial photographs. A selection of 59 maps was accurately analyzed (32 from the sixteenth century, 31 from the seventeenth century, and 6 from the eighteenth century). They were selected by author, commitment, date, and scale, from among more than 1000 maps edited by Savi e Esecutori alle Acque (the ‘hydrographical’ service during the Republic of Venice) in the 16th and seventeenth century. The most representatives (7 from the sixteenth century and 6 from the seventeenth century) were georeferenced and redrawn. Finally, four 1:50.000 maps were created, picturing the ancient morphology and hydrographical network in the years 1550, 1600, 1650, and 1700, covering an area of about 130 square kilometers. Geographical information was compared with historical documents and geological, geomorphological, and geochronological data. Further comparison of geodetic maps from the eighteenth to the twenty-first century produced new maps with important information on the paleogeographical and environmental framework across two centuries, and particularly on the artificial diversion projects performed by the Venetian Republic, their effectiveness, and the geomorphological changes both related to human intervention and recent climatic changes. Keywords: Historical cartography; Lagoon of Venice; alluvial geomorphology; Friuli- Venetian plain; fluvial diversions; Piave River; Livenza River 1. Introduction The ancient hydrographical network and the geomorphological framework of the fluvial and coastal plain between the Livenza and Piave Rivers, located on the northeastern side of the Vene- tian lagoon (Northeastern Italy), has been reconstructed. The present lagoon constitutes a remnant of the old belt of lagoons that used to rim the northern Adriatic coast until the completion of land reclamation projects, which were started in the Renaissance (sixteenth century) and concluded in the period from the end of the nineteenth century to the second half of the twentieth. ∗Corresponding author. Email: [email protected] # 2014 Aldino Bondesan 262 P. Furlanetto and A. Bondesan The mainland of the Venetian lagoon underwent a complex geomorphological transformation triggered by continuous fluvial diversions carried out by the Republic of Venice, mainly during the sixteenth and seventeenth centuries, to drive the main fluvial outlets outside of the lagoon. The oldest maps, dating to the first decades of the sixteenth century, portray a lagoon that is very different from the present setting. The surface area was smaller (about 1/3 of the present surface area) because of subsidence and marine transgressions (Dorigo, 1983; Canal, Cavazzoni, 2004). The marked prevalence of fresh water or brackish water contributed to the rapid burial of large lagoon areas. The change to a more continental environment seems to have been triggered by marine regression enhancing fluvial sedimentation in the lagoon. Progressive sedimentary infilling of the lagoon is attributed by Venetians to fluvial deposition causing a reduction in water-surface area and canal closure. Tidal inlets narrowed and become shallower due to littoral transport of fluvial sands from the deltas belonging to the main rivers discharging into the sea close to the lagoon (Adige, Brenta, and Bacchiglione Rivers, to the south and the Piave River to the north). The result was a state of economic and environmental crisis. As a result the Republic of Venice began a huge program of artificial rivers diversions, lasting almost two centuries and causing changes to both the channels and mouths of the Po, Brenta, Bacchiglione, Marzenego, Sile, Piave, Livenza, and minor rivers. After work on the Bacchiglione, Brenta, and Marzenego (1507–1530), Venice began to divert the course of the Piave River out of the lagoon area on the left side of the river, to both prevent sand from being transported (thereby creating sandbars and shallow water) and to avert floods from affecting Torcello and Murano, causing serious damage to the lagoon. The four maps of the Livenza-Piave plain area (see Main Map) show, from the oldest carto- graphic representation of 1550 to the end of 1600, how the fluvial and coastal system changed during the two centuries when the greatest interventions took place. At the end of the transformations, not only had the hydraulic network changed radically but also the sedimentary dynamics and geomorphological setting of the entire alluvial plain, lagoon, and coastal stretch. 2. Methods The four maps presented herein are part of a wider research project called the Imago (Image Map Archive GIS-Oriented) Project. This project is primarily devoted to the implementation of a data- base concerning 350 historical maps of the Lagoon of Venice and its fringe (Bondesan & Furlanetto, 2012; Fozzati et al., 2012; Furlanetto & Primon, 2004; Furlanetto, Bondesan, Levor- ato, Rosselli, & Bertani, 2009; Furlanetto, Bondesan, Rosselli, Pacquola & Rasador, 2004; Meneghel & Bondesan, 2004; Fontana et al., 2010; Fontana et al., 2014; Francese et al., 2014). The ancient hydrographical and geomorphological context has been reconstructed using historical maps that were georeferenced and overlaid on available geomorphological maps and aerial photographs. The final goal was the diachronic reconstruction of the hydrographic and geo- morphologic changes in the Lagoon of Venice and its hinterland during the sixteenth and seven- teenth centuries: the four presented maps show a part of the study area, in particular, the territory between Livenza and Piave. The project, which began in 2001 and ended in 2011, was funded by Magistrato alle Acque-Consorzio Venezia Nuova – Informative Service of Venice, through a pro- tocol with the National Archives of Venice. The latter has collected more than 100,000 historical maps and related documents, which were issued as fundamental documents for the decree of acts by the Republic of Venice from the fifteenth to the eighteenth century, to exert administrative control over the territory. Esri ArcGis 9.3 was used to georeference all of the studied maps to the same coordinate system (ED1950, Gauss-Boaga projection) and integrate different supporting geodatabases. The main data Journal of Maps 263 came from: (1) geomorphological map (1:20,000; Bondesan & Meneghel, 2004; Bondesan et al., 2004); (2) geological map (1:20,000; Bondesan, Primon, Bassan, & Vitturi, 2008); (3) soil map (1:50,000; Giandon et al., 2001) and (4) a map of the archaeological landscape (1:50,000; Furla- netto, 2012). A comparison was performed through the overlay analysis with topographic maps from the seventeenth to the twenty-first century: the most geometrically accurate being the Topo- graphisch-geometrische Kriegs karte von dem Herzogthums Venedig made by Anton Von Zach in 1797–1805 (Rossi, 2005); the topographic survey of Auguste De´naix (1809–1811); the map of Antonio de Bernardi made in 1843; the Topographic Map of the Lombardo Veneto Reign drawn by the Austrian Imperial Royal General Staff made in 1833 (Austrian General Staff, 1833); and the historical National Topographic Map series (1:25,000 scale) printed by the Geographical Mili- tary Institute since 1861. We also made use of aerial photographs, mainly 1:17,000 to 1:33,000 scale, taken since 1943 and available at the Cartographical Office of the region of Veneto. The thir- teen most-representative historic maps were georeferenced, and the major landforms and geo- graphical information redrawn; through these analyses, four maps at a scale of 1:50,000 were created, depicting historic morphology and hydrology in 1550, 1600, 1650, and 1700. For the georeferenced maps, the root-mean- square error (RMSE)